Manually-operated flexible saws generally are comprised of a series of pivotally-connected cutting teeth in sufficient number to engage a tree limb or other workpiece, connected at each end to ropes or other equivalent means of pulling the saw teeth back and forth over the workpiece from a remote location on the ground. The major distinction between flexible saws and conventional hand saws is the absence of a rigid saw blade. The advantage of the flexible saw is the ability to perform sawing operations on remote tree limbs without the dangers associated with climbing a tree. The disclosed invention improves the known art to achieve a cost-effective apparatus that can be operated efficiently. An objective of the invention is to utilize a standard chain saw blade for cost-efficiency reasons. Examples of prior art such as Prusinski, U.S. Pat. No. 2,752,964; Barausch et al., U.S. Pat. No. 4,242,796; and Meadows, U.S. Pat. No. 3,747,652, all teach a custom-manufactured cutting mechanism. The present invention eliminates the extra cost of custom manufacturing by utilizing a standard flexible linkage chain saw blade, such as the known "Oregon" type. Use of standard materials is also cost effective from a maintenance (sharpening) and replacement standpoint.
One problem not resolved by prior art is the proper positioning of the blade on the workpiece. An important element of sawing with a flexible blade is the positioning of the blade on the workpiece in such a way as to achieve maximum results from the initial downward pulls. Proper positioning is often difficult to achieve, because the operator cannot manually place the saw blade in proper position from his remote location. Often, a segment of rope close to the blade often becomes snagged on bark or wedged within the juncture of the branch and tree trunk. Friction and snagging is minimized with the present invention by use of a string of roller beads near the blade at the point of engagement with the workpiece. Roller beads are substantially spherical objects strung over the rope loosely so as to permit the beads to roll around the axis of the rope.
Another problem associated with blade orientation is the position of the cutting teeth on the workpiece. Flexible link sawing teeth will assume a vertical plane when draped over a tree limb. The links will remain in that orientation when oscillated over the workpiece by force of the operator alternately pulling on the ends of the ropes. However, it is important to position the blade with the cutting teeth opposing the workpiece. Barausch and Prusinski teach cutting blades that operate in either orientation but suffer from the cost and efficiency factors mentioned above. Johnson, U.S. Pat. Nos. 4,240,203 and 4,344,229, teaches a counterweight that facilitates assumption of an untwisted vertical plane when draped over the workpiece but does not ensure proper placement of the cutting teeth in opposition to the workpiece. This often requires multiple attempts to position the blade properly. The present invention discloses a tipping device containing a rigid flag member that tips the saw blade into proper orientation if initial placement results in the cutting mechanism pointing away from the workpiece. The roller beads assist in vertical and horizontal movement of the apparatus over the workpiece, thereby easily achieving proper placement of the tipping device and saw blade.
Other improvements that facilitate ease of operation are adjustable ropes combined with handles or other equivalent means for grasping the ropes to maximize the efficiency of the alternating downward pulls by the operator. Cutting can be achieved at any angle and at a safe distance from the workpiece. An adjusting block on each rope permits the ropes to be shortened or lengthened as necessary, thereby preventing the unrequired length of rope from accumulating on the ground at the feet of the operator, thus minimizing the potential hazard of entanglement with the operator's feet during normal operation or a retreat from falling debris. This invention also discloses a pole and hook for placing the saw over the workpiece more efficiently than with the forked pole taught by Barausch or by using the counterweights taught in Johnson to help in throwing one end of the saw over the workpiece. The hook is of a U-shaped configuration that allows the operator to drop one end of the saw over the workpiece by merely rotating the pole.